Monthly Archives: June 2012

Dear Dr. K: It seems as if medical research often countermands itself. First we hear niacin improves lipid health, then that it doesn’t affect health outcomes. Medicine for osteoporosis is deemed good; then we learn it might make brittle bones. Is there any research we can believe?

I understand your concern and confusion and will try to provide practical answers.

First you have to realize we live in an informational society grounded in instant dissemination of ideas through a variety of media and the Internet. Keep in mind there is a difference between information, knowledge, and then, wisdom.

In a way each is a step in the process of true and accurate understanding. Often, simple data or information is misconstrued because of lack of applicable knowledge or true wisdom.

For instance it is known that lower lipid values have health benefit. It also is known that niacin lowers lipid values. Unfortunately a simple assumption was made that, therefore, niacin must have health benefits. The first two bits of information were simple data that unfortunately led to an incorrect assumption.

Eventually, health outcome studies with niacin therapy were done. It was at this point that knowledge replaced data in that these studies failed to show a clinical health benefit, despite better laboratory numbers.

All scientific endeavors move forward by fits and starts. Hypotheses are made, data are collected and then theories are proposed. What can seem to be a solid theory can later be disproved or refined.

A good case in point is Newtonian physics — the principles of which work well enough to have allowed the success of the Apollo missions to the moon, but are unable to properly handle phenomena that approach light speed. For that we need Einstein’s principles of space and time.

Instead of being disheartened when new research changes previous beliefs, be glad that truth is being continually sought, however circuitous the path may be.

This month’s issue of the Journal of Allergy and Clinical Immunology has a symposium on food allergy.

Until recently it has been recommended that a good strategy to reduce risk of children developing food allergy was to promote exclusive nursing as a food source, to have the mother avoid highly allergenic foods and to delay weaning with introduction of solid foods.

However, despite the implementation of this approach in a number of countries in Asia, Europe and North and South America, there has been no reduction in the incidence of food allergy. The recommendations were made based on individual facts that are true, but that unfortunately do not lead to the desired outcome.

It is definitely true that mother’s milk is the best and most complete of infant nutrition. It is also true that mother’s milk contains a host of proteins and immune globulins that provide protective immunity to the infant. It is also true that early exposure to foods other than mother’s milk can lead to the development of food allergy.

From all these facts it was assumed the feeding recommendations also would be the best course to follow.

Once the potential benefit of this dietary approach was actually studied however, it was quickly learned that it did not provide the desired results. As it turns out a crucial fact that was previously unknown makes a pivotal difference.

If infants have early exposure to non-breast milk foods through skin contact, this is what leads to allergic sensitization. This has been born out in animal model research. Paradoxically, the food allergy development through skin contact can actually be prevented by early oral exposure to the food, e.g., from parents’ hands, kisses, etc. A good example of this phenomenon has actually been recognized for quite some time and it has to do with nickel allergy.

If a child’s first exposure to nickel is from pierced ears (skin exposure), there is up to a 40 percent chance of the child developing nickel allergy. If, on the other hand the child has oral nickel exposure from placement of orthodontic braces prior to ear piercing, the risk of nickel allergy is almost zero.

At this point in time the American Academy of Allergy has no specific recommendation. There are, however, numerous randomized controlled studies that are being conducted comparing the early exposure to foods such as peanut, milk, wheat and egg versus strict avoidance of these foods. Such studies will lead to a new evidence-based recommendation on how to prevent food allergy.

Another part of the Journal of Allergy and Clinical Immunology’s food allergy symposium addressed European research on food vaccines. Impetus for this research is the worldwide increase in food allergy and also the increasing frequency of anaphylactic shock from food allergy.

Since vaccine therapy has proven successful in treating respiratory allergies and has also worked to prevent recurrent anaphylaxis from insects, it stands to reason that it could help eliminate food allergy and prevent food-related anaphylaxis.

Four types of vaccines for food allergy have been studied in Europe (and other countries): oral, sublingual, epicutaneous and subcutaneous.

All of these methods have proven to be of some benefit. Unfortunately, the ones that lead to the best improvement seem to have more side effects. Between the two ingestion vaccines (immunotherapy), oral immunotherapy leads to better reduction in allergy than sublingual.

The oral route commonly leads to GI side effects such as heartburn, nausea, vomiting, cramps and diarrhea. The sublingual route was much less likely to cause these symptoms, but did lead to itching and swelling in the mouth. Epinephrine shots had to be given twice as often for reactions in the oral group as compared to the sublingual group.

But patients who were successfully treated from both groups were able to ingest the implicated food – such as peanut – without going into allergic shock.

Subcutaneous immunotherapy, which is how traditional allergy shots are given, was more effective than epicutaneous immunotherapy. But once again, the more effective format led to more frequent vaccine reactions and to greater need for epinephrine to treat some of the reactions. When either of these techniques was successful, it again allowed the patient to safely ingest the offending food.

The European study group is conducting new and longer studies of these various forms of immunotherapy. The studies will include children, adolescents and adults. They also are adding studies to compare the use of pharmaceutical-grade food extracts versus the use of the entire native food as a vaccine substrate to see which works better and is safer.